Combined pelvic and para-aortic is superior to only pelvic lymphadenectomy in intermediate and high-risk endometrial cancer: a systematic review and meta-analysis.

Background: Lymph node metastasis is a principal prognostic factor for the treatment of endometrial cancer. Added value of para-aortic lymphadenectomy to only pelvic lymphadenectomy for intermediate/high-risk endometrial cancer patients remains controversial.
Objective: A systematic review and meta-analysis was performed to assess the impact of combined pelvic and para-aortic lymph node dissection (PPALND) compared to only pelvic lymph node dissection (PLND) on survival outcomes of intermediate and/or high-risk patients.
Study Design: The systematic review and meta-analysis adhered to the PRISMA guidelines for meta-analyses of interventional studies. Pubmed, Scopus, EMBASE and Cochrane were searched up to April 20, 2018. Included studies were those comparing high-risk endometrial cancer patients that had performed pelvic and para-aortic lymph node dissection (PPALND) vs. only pelvic lymph node dissection (PLND) apart from standard procedure (total hysterectomy with bilateral salpingo-oophorectomy, TAHBSO). Primary outcomes of the study were overall survival and disease-free survival rates. Methodological quality of the included studies was assessed using the ROBINS-I tool. Overall quality of the evidence for the primary and secondary outcomes was evaluated as per GRADE guideline using the GRADE pro GD tool.
Results: There were 13 studies identified with 7349 patients included. All studies were retrospective observational as no RCTs or prospective studies adhering to inclusion criteria were retrieved. Combined pelvic and para-aortic lymphadenectomy was associated with 46% decreased risk for death (HR 0.54, 95% CI 0.35-0.83, I ²  = 62.1%) and 49% decreased risk for recurrence (HR 0.51, 95% CI 0.28-0.93). It was also associated with increased 5-year OS rate (RR 1.13, 95% CI 1.04-0.24, I ²  = 57.3%) and increased 5-year DFS rate (RR 1.23, 95% CI 1.14-1.31, I ²  = 85.5) compared with only pelvic lymphadenectomy.
Conclusion: Combined pelvic and para-aortic lymphadenectomy is associated with improved survival outcomes compared with only pelvic lymphadenectomy in women with intermediate/high-risk endometrial cancers. Further prospective studies should be performed.